1. Field of the Invention
This invention relates to an improved wheel assembly and wheelchair, and in particular to a wheel assembly having multiple small rotatable wheels mounted laterally on a main wheel whereby lateral movement as well as forward and backward movement is possible.
2. Description of the Prior Art
Wheelchairs are available in a variety of shapes and sizes. The traditional wheelchair design, whether powered, manual or pushed by another person, has two main, large diameter, side mounted wheels having fixed parallel positions and having hand rails attached thereto. Because of the fixed parallel positions of the main wheels, movement is generally restricted to pivoting, straight line or curved movement. Curved and pivoting movement is attained by rotating the main wheels at different speeds or in opposite directions. However, the wheelchair cannot achieve side-to-side lateral motion.
In order to shift position laterally, a wheelchair operator must back up, pivot, move forward, pivot, and move forward again. This may be tolerable in some situations; however, the inability to move laterally causes significant difficulty in maneuvering in tight quarters such as bathrooms and elevators. Even in a confined office or work setting, the constant backing and pivoting is time consuming and unproductive.
Transport wheelchairs utilizing four small wheels that rotate have been developed that enhance mobility in tight quarters. However, this type of chair requires the constant presence of an assistant since it cannot be hand propelled.
Thus, there is a need for hand-propelled wheelchairs that can be moved laterally as well as in the standard forward-reverse movement. There is also a need for a wheel assembly that can move laterally as well as forward and backward.